| 摘要 |
PURPOSE:To secure stable wear resistance and excellent sliding on a surface contact with an original, by providing a spacer layer, which is arranged so as to specify the distance between an optical sensor and the surface of the original and to cover the optical sensor, and providing a surface layer, whose friction coefficient is smaller than that of the spacer layer. CONSTITUTION:A spacer layer 129 is provided. A surface layer 132 is provided at a surface contact with an original P thereon. Thus protection layers have a double-layer structure. A function as a spacer between a light receiving part and the original P is provided. Deterioration due to contact with the original P and wear of the light receiving part is prevented. Therefore, it is desirable that the spacer layer 129 comprises a material, which has excellent light transmitting property and can be formed at a uniform film thickness. For example, photoset resin, thermoset resin, light sensitive resin and the like are desirable. Meanwhile, it is necessary that the friction coefficient of the surface layer is smaller than at least that of the spacer layer. As a material that can be selected for the surface layer, e.g., plastic material having a low friction coefficient is listed. In order to form a protective layer from the spacer layer and the surface layer, e.g., the surface layer is thinly laminated on the spacer layer. |
